For perspective: there was a power outage that took place across the Iberian peninsula (affecting mainly Portugal and parts of both Spain & France back in 2025), at least people there didn't resort to looting immediately the moment everything was in disaray (transit networks were down, internet & phone connections were offline, contactless payments were disrupted and people were made to leave public venues). At least, the federal governments of their countries managed to act fast the moment this occurred nationwide.

It would be extraordinarily unlikely, because the power grid of the US and Canada are not one thing.

Separate regional power grids all have their own management. The northeast US and Eastern Canada did have a major power outage years ago and it was managed about as well as any other major outage.

Texas has its own isolated grid and it lost power for a while when a stronger than expected winter storm hit. It was a bit of a shitshow because the state isn't set up to handle that kind of weather.

So the answer is just like any other question about the Americas - depends on which region is in charge of it, and why it happened. The US does have a federal government, but for MOST things the federal government is only in charge of supporting the states, not running them.

In the US, the power grid is split in 3: East, West, and Texas. For all three to go down would probably mean terrorism or war, so the military response would be relatively quick. If we ignore that and restrict response to mean relief for citizens, we have a recent record of federal response times for a Texas crisis: 4 days. It took two days for Texas to declare an emergency and two more days for the federal government to declare one on the federal level and send additional help. https://en.wikipedia.org/wiki/2021_Texas_power_crisis

They only need to get two then, Texas will take care of itself.

If there is a continent wide black out the government is likely going to be the cause of it to begin with.

https://en.wikipedia.org/wiki/Northeast_blackout_of_2003

I remember this one well. We were without power for two and a half days. I got together with a bunch of friends and we went to each other's homes and barbequed all the food that was spoiling, smoking a fuckton of weed in between stops. Our small Ontario town turned into one big street party. The only shitty part was it happened during a heat wave so sleeping was a little rough.

Well, the professionals are going to get to work and respond essentially immediately. However, leadership of the U.S. is going to make it into a political issue immediately and slow down that response and actions to support states, cities, and communities that need it based on political lines

And the next thing we'll see is:

We'll assist in restoring power to states that ban mail-in voting.

Or similar corruption

It's really not that uncommon here in Canada. State of emergency gets declared and we just go about our business. North East US did fine in '03. Texas was ugly when their grid went down not so long ago, but I think that was more from the snow. They're not really used to a real winter, so when it started snowing at the same latitude as Bagdad, it kind of freaked them out.

At least here in Canada we're kind of used to nature trying to kill us. My friend used to joke "when Texans say 'this is God's country' they mean God made this land just for us. When Canadians say 'this is God's country' they mean this is the land he was keeping for himself, and he's not happy about us sleeping on his couch."